Last year I decided to learn to do a hat,and debated between two patterns. Ultimately chose one, and was amazed to find I'd knitting what my family affectionately calls "Gargantua Hat" because I used the needles from one pattern on the other pattern (10's instead of 7's!)
So, I finally got around to trying again, and am quite proud of myself. Did it in 2 days, too!
The pattern is "allison's beginner cap."